Recent advances in potassium persulfate (K2S2O8)-mediated C C, C–heteroatom, and heteroatom–heteroatom bond formations

Potassium persulfate (K 2 S 2 O 8 ) has emerged as a highly versatile, sustainable, and practical oxidant in modern organic synthesis, enabling the efficient construction of C C, C–heteroatom (C N, C O, C S, C P, etc.), and heteroatom–heteroatom (N N, S S, N O, etc.) bonds under mild and often metal-free conditions. Since 2021, significant advances have been reported in K 2 S 2 O 8 -mediated transformations, including oxidative couplings, C H functionalization, O -sulfation of alcohols and oximes, thiolation and selenylation of carbazoles and pyrazoles, selective phosphorylation of heteroarenes, and the synthesis of sulfonamides and sulfenamides. These methodologies demonstrate broad substrate scope, high efficiency, operational simplicity, and environmental compatibility, often proceeding via radical pathways with or without synergistic use of transition metals, photoredox catalysts, or electrochemical systems. This review summarizes K 2 S 2 O 8 -mediated reactions and mechanistic advances reported from 2021 onward, emphasizing their synthetic utility and substrate scope while demonstrating the growing use of K 2 S 2 O 8 as a practical, inexpensive, water-compatible, and relatively low-toxicity oxidant in organic synthesis.